Cylinder head of an air-cooled internal combustion engine

ABSTRACT

A cylinder head of an air-cooled internal combustion engine which is provided with a pressure oil channel for the additional cooling of places in the cylinder head that are particularly subjected to thermal stresses; on the inside of the cylinder head the pressure oil channel passes over into a hollow space whereby cooling ribs are arranged at the inner walls of the hollow space.

States Patent [72] Inventors Otto Herschmann,

Schorndorf, A Josef Reisacher, fellbachlingoglgjsch, yStuttgart-Rohracker, and Alfred Goetz,

Stuttgart, Germany [2l] Appl. No. 722,611

[22] `Filed Apr. 19, 1968 [45] li'atentedv Jan. l2, 1971 [73] AssigneeDaimler-Benz Aktiengesellscha 1. Stuttgart-Unterturkheim, Germany [32]Priority Apr. 22, 1967 [33] Germany [3 l No. D52898 [54] CYLINDER-HEADOFAN AIR-COOLED INTERNAL COMBUSTION ENGINE 13 Claims, 2 Drawing Figs.[52] U.S.`(`I .1 12B/41.42, l23/4l.55, l23/4l.57 [5l] Int. Cl Flllp3/04,

.Primary Examiner-Mark Newman Attorney-Craig, Antonelli, Stewart & HillABSTRACT: A cylinder head vof an air-cooled internal combustion enginewhich is provided with a pressure oil channel for the additional coolingof places in the cylinder head that are particularly subjected tothermal stresses; on the inside of the cylinder head the pressure oilchannel passes over into a hollow space whereby cooling ribs arearranged at the inner walls of the hollow space.

' 4PATENTED JAN T 2 Isn SHEET- 1: OT 2 TNVENTORS OTTO HERSCHMANN JOSEFREISACHER HENZ STOCKFISCH ALFRED OOTZ M ATTORNEYS PATENTEUJAmmn-3.554171 snm e or 2 OTTO HERSCHMA f F REISACHER Z STOCKFISCH ALFRED GOTZdu? Z ATTORNEYS CYLINDER HEAD F AN AIR-COLED INTERNAL COMBUSTION ENGINEBACKGROUND Ol: THE INVENTION SUMMARY or THE INVENTION lncontradistinction thereto, the present invention aims at intensivelycooling bymeans of pressure oil the thermally maximal stressed area ofthe cylinder head, especially of high performance engines; This takesplace according to the present invention in that'v the pressureoil'channel passesover into a hollow space arranged on the inside of thecylinder head, at the interior walls of which arearranged cooling ribs.

A particularlyy effective heat transferor heat removal is achieved inaccordance with the present invention in that the cooling ribs, startingfrom wall parts of the hollow space that are particularly heated up,intermesh or interengagewith one another in such a manner that incooperation with a filler piece` protruding into the hollow space ameander-shaped guidance of the cooling oil streamresults.

Accordingly, itis an object of the present invention to pro vide acylinder head `for an air-cooled internal combustion engine whichavoids, by` simple means, 'the-shortcomings and drawbacks mentionedhereinabove and encountered in the prior artconstructions. v l

Another object of the present invention resides in a cylinder head ofair-cooled internal combustion engines, especiallyfof highperforrnanceengine's in which the areas of the cylinder head that aresubjected to maximum thermal stresses are effectively and intensivelycooled. y n

A further object of the present invention resides in a cylinder head ofan air-cooled internalcombustion engine in which an efficacious heatremoval is achieved by simple and relatively inexpensive means.`

Still another object of the present'invention resides in a cylinderheadof an air-cooled intemal-combustion enginef which is simple inconstruction, easy to assemble and reliable in operation for theintended purposes.

Still a further object of the present invention resides in a cylinderhead for an air-cooled internal combustion engine which assureseffective cooling without the need for any additional supply pump'or oilcooler other than those already necessitated for the lubricatingcirculatory system. j

A further object of the present invention resides in a cylinder head ofan air-cooled internal combustion engine which is provided with anapproximately meander-shaped pressure oil channel effectively avoidingdead spaces for the cooling oil. i v

These and further objects, features, and advantages of thepresentinvention will become more obvious from the following descriptionwhen taken in connection with the accompanying drawing which shows, forpurposesof illustration only, one embodiment in accordance with thepresent invention, and wherein: 4

FIG. l is a partial cross-sectional view through an installed cylinderhead of an air-cooled Dieseliengine in accordance with the presentinvention, taken alongline -l-lof FIG. 2; and

FIG. 2 is a partial cross-sectional view'through the cylinder covered bycontrol housing 13 enclosing the conventional control devices, such asrocker arms. etc. A conventional seal is interposed between the cylinderhead ll and the control housing 13.`Clampng or tightening bolts 16starting from the control housing 13 extend through througlvbores 17(FIG. 2) in the cylinder head 1l.and'are guided through correspondingapertures at the cylinder-l2 and connect these structural parts with thecrankcase (not shown An inlet channel 18, an exhaustchannel 19 and abore 20 for the accommodation of an injection nozzle (not shown) arearranged in the cylinder head 1l. Ribs 21', 22 and 23 extend from thecylinder head ll for the purpose of air-cooling. Through-bores 24 andapertures 25 for the pushrod protective tubes 26 are provided in theribs 22.

The first partial section 27 (FlG. l of a pressure oil channelterminates in a hollow space 28 and is continued in a further partialsection 29 from which branches off at right angle in the .upwarddirection the partial section 30..A channel 31 in the control housing 13adjoins the `partial section 30. A closure screw 32 closes the end ofthe partial section 29. Threaded connecting nipples 33 and 34 aredisposed at the beginning of the partial section 27 of the channel and,at the end of the channel 31, respectively.

The hollow space 28 is arranged in the cylinder head ll above the webbetween the inlet channel 418 and the exhaust channel 19. Cooling ribs36 and 37 start from the bottom 35 (FIG. l) of the hollow space 28. Thecooling ribs 36 extend in part from the lateral wall 38 up to thelateral wall 39 (FIG. 2) of the hollow space 28. The cooling ribs 37 areconnected only with the lateral wall 39 and are constructed higher. Asteppeddown or shoulderedoff tiller piece 4l; arranged at the bottomside 40 of the control housing 13, extends up to the upper edges of thecooling ribs 36 and 37 and closes off the hollow space 28 in the upwarddirection. The filler member 41 may, as shown in the drawing, beconnected in one piece with the control housing 13 or may besecured atthe same time, for example, by screws or bolts.

The illustrated cooling oil circulatory system of the cylinder head l1is connected in parallel to the conventional lubricating oil circulatorysystem (not shown) of the internal combastion engine. A separate supplypump and a further oil cooler can be saved as a result thereof. Thesupply line branching off from the lubricating oil circulatory system isconnected with the connecting nipple 33 while the return line isconnected to the connecting nipple 34. During operation, the pressureoil flows through the partial section 27 of the channel into the hollowspace 28. Thecooling ribs 36 and 37 arranged transversely to the mainflow direction. together with the stepped filler piece 4lextendng up tothe upper edges of the cooling ribs, impose upon the cooling oil streama meander-shaped path both in a parallel plane to the bottom 35 of thehollow space 28 as-also in a parallelV plane to the lateral wall 39;Dead spaces, in which the cooling oil can collect and dam up, areavoided thereby. lt is possible in this manner to remove or carry o a.maximum amount of heat from the parts' of the cylinder head which areparticularly subjected to thermal stresses, i.e., above all from the webbetween the inlet channel 18 and the outlet channel 19. After leavingthe hollow space 28, the pressure oil flows through the partial sections29 vin accordance with thepresent invention, it is understood that thesame is not limited thereto but is susceptible of numerous changes andmodifications asknown to a person skilledin the art.' For example,instead of one hollow space equipped with herein but intend to cover allsuch changes and modifications as are encompassed by the scope of theappended claims.

We claim:

l. A cylinder head for an air-cooled internal combustion engine providedwith air-cooling means and a pressure oil channel for the additionalcooling of places in the cylinder head that are particularly subjectedto thermal stresses, characterized in that during engine operation apressurized oil stream flows through the pressure oil channel and passesover into a hollow space provided on the inside of the cylinder head,and cooling rib means are arranged at the inner walls forming saidhollow space.

2. A cylinder head according to claim l, further comprising filler meansextending into the hollow space, the cooling rib means so engaging withone another that in conjunction with said ller means an approximatelymeander-shaped guidance of the cooling oil stream results.

3. A cylinder head according to claim 2, wherein said cooling rib meansstan from those wall parts that are particularly subjected to heatstresses.

4. A cylinder head according to claim 3, wherein said cooling n`b meansengage alternately with each other in such a manner that saidmeander-shaped guidance for the cooling oil stream results.

S. A cylinder head having a control housing mounted on the cylinder headaccording to claim 4, wherein said filler means is arranged at thebottom side of the control housing.

6. A cylinder head provided with a web between its inlet channel and itsoutlet channel according to claim 5, characterized in that said hollowspace is arranged above said web.

7. A cylinder head according to claim 6, wherein the engine includes alubricating circulatory system, and wherein said pressure oil channel isoperatively connected with said lubricating oil circulatory system.

8. A cylinder head provided with a web between its inlet channel and itsoutlet channel according to claim l, characterized in that said hollowspace is arranged above said web.

9. A cylinder head according to claim l, wherein the engine includes alubricating circulatory system` and wherein said pressure oil channel isoperatively' connected with said lubricating oil circulatory system.

l0. A cylinder head according to claim l. characterized in that saidhollow space extends through the cylinder head only within the areasthereof subjected to very high thermal stresses.

ll. A cylinder head according to claim l0. characterized in that saidhollow space extends through the cylinder head only within the areathereof disposed between its valve channels.

l2. A cylinder head according to claim l, characterized in that saidchamber is limited to the area between the valve channels of thecylinder head.

13. A cylinder head according to claim l, characterized in that said oilchannel is of relatively small cross section compared to the crosssection of the cylinder head in a plane ex tending through said oilchannel.

1. A cylinder head for an air-cooled internal combustion engine providedwith air-cooling means and a pressure oil channel for the additionalcooling of places in the cylinder head that are particularly subjectedto thermal stresses, characterized in that during engine operation apressurized oil stream flows through the pressure oil channel and passesover into a hollow space provided on the inside of the cylinder head,and cooling rib means are arranged at the inner walls forming saidhollow space.
 2. A cylinder head according to claim 1, furthercomprising filler means extending into the hollow space, the cooling ribmeans so engaging with one another that in conjunction with said fillermeans an approximately meander-shaped guidance of the cooling oil streamresults.
 3. A cylinder head according to claim 2, wherein said coolingrib means start from those wall parts that are particularly subjected toheat stresses.
 4. A cylinder head according to claim 3, wherein saidcooling rib means engage alternately with each other in such a mannerthat said meander-shaped guidance for the cooling oil stream results. 5.A cylinder head having a control housing mounted on the cylinder headaccording to claim 4, wherein said filler means is arranged at thebottom side of the control housing.
 6. A cylinder head provided with aweb between its inlet channel and its outlet channel according to claim5, characterized in that said hollow space is arranged above said web.7. A cylinder head according to claim 6, wherein the engine includes alubricating circulatory system, and wherein said pressure oil channel isoperatively connected with said lubricating oil circulatory system.
 8. Acylinder head provided with a web between its inlet channel and itsoutlet channel according to claim 1, characterized in that said hollowspace is arranged above said web.
 9. A cylinder head according to claim1, wherein the engine includes a lubricating circulatory system, andwherein said pressure oil channel is operatively connected with saidlubricating oil circulatory system.
 10. A cylinder head according toclaim 1, characterized in that said hollow space extends through thecylinder head only within the areas thereof subjected to very highthermal stresses.
 11. A cylinder head according to claim 10,characterized in that said hollow space extends through the cylinderhead only within the area thereof disposed between its valve channels.12. A cylinder head according to claim 1, characterized in that sAidchamber is limited to the area between the valve channels of thecylinder head.
 13. A cylinder head according to claim 1, characterizedin that said oil channel is of relatively small cross section comparedto the cross section of the cylinder head in a plane extending throughsaid oil channel.